gpiolib: iron out include ladder mistakes

The <*/gpio.h> includes are updated again: now we need to account
for the problem introduced by commit:
595679a8038584df7b9398bf34f61db3c038bfea
"gpiolib: fix up function prototypes etc"

Actually we need static inlines in include/asm-generic/gpio.h
as well since we may have GPIOLIB but not PINCTRL.
Make sure to move all the CONFIG_PINCTRL business
to the end of the file so we are sure we have
declared struct gpio_chip.

And we need to keep the static inlines in <linux/gpio.h>
but here for the !CONFIG_GENERIC_GPIO case, and then we
may as well throw in a few warnings like the other
prototypes there, if someone would have the bad taste
of compiling without GENERIC_GPIO even.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

include/linux/gpio.h

@@ -231,21 +231,20 @@ static inline int irq_to_gpio(unsigned irq)
 	return -EINVAL;
 }
 
-#ifdef CONFIG_PINCTRL
-
 static inline int
 gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
 		       unsigned int pin_base, unsigned int npins)
 {
+	WARN_ON(1);
+	return -EINVAL;
 }
 
 static inline void
 gpiochip_remove_pin_ranges(struct gpio_chip *chip)
 {
+	WARN_ON(1);
 }
 
-#endif /* CONFIG_PINCTRL */
-
 #endif /* ! CONFIG_GENERIC_GPIO */
 
 #endif /* __LINUX_GPIO_H */